Sanding roller



W. A. F. BOETTCHER SANDING ROLLER Filed March 11, 1931 Patented Oct. 2, 1934 STATES PATENT OFFICE Application March 11,

4 Claims.

My invention relates to rollers carried by floor sanding machines, said rollers being wrapped by a sheet of sand paper, and my main object is to so design a roller of this kind as to dispose the sand paper sheet in a true circular course.

A further object of the invention is to cut the sandpaper sheet with a form to present circular prominence when the sheet is wrapped on the roller at any point of contact between the roller and the floor.

A still further object of the invention is to so improve the roller and its sandpaper wrapping that joints in the sandpaper sheet do not affect the uniformity of contact between the roller and the floor.

A final but nevertheless important object of the invention is to design the novel roller and sandpaper sheet on lines of utmost simplicity consistent with their structural and functional nature.

With the above objects in view and any others that may suggest themselves from the specification and claims to follow, a better understanding of the invention may be had by reference to the accompanying drawing, in which Fig. 1 is a longitudinal section through the wrapped sanding roller, preferably taken on the line 1-1 of Fig. 2

Fig. 2 is a cross section of the same; and

Fig. 3 is a plan view of the developed sandpaper sheet.

The conventional sanding roller is wrapped in a rotary direction with the sandpaper sheet, the ends of the sheet meeting and being tucked into a longitudinal slot in the periphery of the roller. Within this slot are means for securing one end of the sheet and drawing upon the other end thereof whereby to snugly wrap the sheet around the roller. While a roller so wrapped is eflicient in a general way, a closer scrutiny of the work done by it reveals a rippled effect, this being due to the fact that the peripheral prominence of the sanding sheet is somewhat deficient at the line of the sheet joint. In effect, the roller experiences a slight fall each time this line meets the floor, so that the consequent rise of the roller is manifested momentarily by a deeper cut, causing the ripple. In the novel roller, I have so divided the sheet-securing zone and designed the sheet that the above difficulty is overcome.

Referring specifically to the drawing, it will be seen that the roller 5 is fundamentally of standard design, having the usual shaft 6 for an operative connection with the machine. I also employ the standard securing elements for the sand- 1931, Serial No. 521,822

paper sheet, as represented by an abutment 7 and a cam 8 mounted on'the shaft 9. In the standard roller, the latter has but one longitudinal split, while in my roller only the end portions of the split are made in one zone while the middle portion is made as a split diametrically opposite from the original zone. Thus, as the roller is turned, one sees two laterally spaced slots in the periphery, such slots extending adjacent to the ends of the roller, and when the roller is turned 180 further, a medially positioned slot is seen.

As indicated in Fig. l, I use a pair of securing units on a single shaft in connection with the lateral slots as seen in the upper part of the figure; and I use a single securing unit in connection with the medial slot as seen in the lower part of the figure.

In order to utilize the securing units as arranged in the novel manner described, I cut the sandpaper sheet as indicated in Fig. 3. In wrapping this sheet around the roller, I apply its side portions A to the lateral slots of the roller, and its medial portion B to the medial slot thereof. Folding lines C are indicated for the ends of the portions A and a folding line D is indicated for the projecting end of the portion B. Thus, the tabs defined by the folding line C are tucked into the lateral slots of the roller when the sheet has been wrapped around the same and the tab defined by the folding line D is similarly applied to the medial slot. Now when the shafts of the securing device are rotated by suitable means, such as a screw in socket 10 terminally of the shafts, the portions of the sandpaper sheet may be drawn up to snugly wrap the sheet around the roller.

It will be noted that only one end of the portion B of the sandpaper sheet is secured in the roller. .By noting the direction of rotation of the latter, as indicated by arcuate arrows in Fig. 2, it will be seen that the projecting end is the frontal one. Hence, as this action draws the medial portion of the sheet into close contact with the roller, it is unnecesary to have the rear end of the portion anchored in the roller slot.

With the roller and sandpaper sheet designed and combined as described, it will be clear that at no time is there a complete split or dent longitudinally of the wrapping periphery. In other words, when the joint of the portions A is evident, the smooth or entire course of the portion B acts as a filler; and when the joint of the section B is visible, then the continuity of the portions A is co-existent. Thus, when the roller is on the floor,

it always has an area of peripheral entirety or prominence in contact with the floor, such area bridging the fall that would otherwise be suffered by the roller through the presence of a sandpaper joint. Hence, with the roller always in uniform spacing from the floor, the efiect on the floor is also uniform, eliminating ripples or other irregularities. My improvement nullifies the momentary fall of the roller which is induced by the conventional full length joint, and makes the roll er operate as if its wrapping had no joint at all. Finally, it will be obvious that the novel roller could be manufactured with Very little more eX+ pense than the standard one, since the change involves but a repetition of old principles by lending the securing units a new arrangement; also, the sandpaper is easy to cut in the new pattern and causes no waste, as may easily be seen from the pattern of Figure 3, which could be cut in immediate succession from a ribbon of material and without any blanks or other waste.

I claim:-

1. A sanding implement comprising a roller, a sheet of sandpaper wrapped therearound until its ends are in opposed relation, said wrapper having lateral and medial sections, and the latter being rotarily advanced from the lateral sections to present a continuous peripheral portion opposite the ends of the lateral sections.

2. A sanding implement comprising a roller formed with a longitudinal series of recesses, these being out of consecutive registration, and a sandpaper sheet wrapped around the roller until its ends are in opposed relation, such ends being in the form of divisions corresponding in length and position to said recesses, and tabs projected from said ends into the respective recesses to be secured therein.

3. A sanding implement comprising a roller formed with a longitudinally spaced series of recesses on one side, and with a similar and alternating series of recesses on the diametricallyopposite side, and a sandpaper sheet wrapped around the roller until its ends are in opposed relation, such ends being in the form of divisions corresponding in length and position to said recesses, and tabs projected from said ends into the respective recesses to be secured therein.

4. VA sanding implement comprising a roller, a

sheet of sandpaper wrapped therearound until its ends are in opposed relation, one end of the sheet having a recess, an extension of the other end into said recess, the roller being form d with cavitiesopposite the remaining end portions of the sheet and the free end of the extension, and tabs projecting from said-remaining end portions and tree end into the respective cavities to be secured therein.

WILLIAM A. F. BOETTCHER. 

